Crossing small creeks and drainages

I have been feeling kind of stuck lately on exactly what I was doing with the area on the east or left end of the Wesso section.  In the recent post Land contours for the Wesso section I had shown how I created an area for a river bed.  I had thought of using some bridges to make this the first crossing of the Humboldt River but because this is on a curve I realized that would not work so well so I came up with another idea.

Besides using various types of trestles and bridges to cross the larger rivers, the railroads use several types of culverts to cross smaller creeks or other types of low laying areas that provide seasonal drainage.  With the tracks of both the SP and WP built up as they are there are in this location there are many places that use these culverts.

Several model kits are available in N scale to model a box type concrete culvert.  I was drawn to this one by Blair Line because I like the year of construction being part of the structure.  I plan to use this for the SP track in the background and then perhaps use a low wood trestle for the WP track in the foreground.

In this photo I am partially filling in the riverbed with insulation board scraps.  The assembled box culvert kit and some track are temporarily in position while the Liquid Nails holding the insulation board scraps in place is drying.  In the foreground the WP right of way is in the process of being re-aligned and will cross this area on a low wood trestle.